This invention relates generally to conveyor systems and, in particular, to systems which receive packages in a cluster including side-by-side packages and which rearrange the packages into a single file, singulated stream.
In U.S. Pat. No. 5,415,281, which is commonly assigned with the present application, an article singulation conveyor is disclosed which utilizes tapered rollers which are driven at a uniform speed for the length of the conveyor but which produce a continuous speed increase laterally towards a vertical belt. The tapered rollers may be divided up into plural lanes of rollers. The speed increase across the conveyor bed tends to arrange packages in single file because one of a pair of side-by-side packages will move ahead of the other as both are urged in the direction of the vertical belt. The device disclosed in this patent is exceptionally effective if provided in sufficient length, such as 60-foot sections.
Some conveyor installations are restricted in the amount of space available for singulating clusters of packages. This is particularly a problem with modifications to existing installations, as well as new installations in existing facilities which are often constrained on space.
Rearrangement of clusters of articles into singulated single file is especially difficult for packages having one dimension that is significantly greater than its other dimensions. If several such long and slender articles are conveyed side-by-side, conventional article singulation conveyors have difficulty breaking up the side-by-side pair into single file. This is an especially onerous task in a singulation conveyor that is relatively short in length. Another problem that can occur is that packages having one long dimension can get oriented on the output of the singulation conveyor with the long dimension transverse the direction of travel of the conveyor. This can provide package jams, especially if the long dimension of the package is wider than a conveyor downstream of the singulation conveyor.
Thus, the need exists for a compact article singulation conveyor, or unscrambler, which is exceptionally effective in separating side-by-side packages into a single file of singulated articles without requiring a long footprint. Such a compact article singulation conveyor must be capable of breaking up pairs of side-by-side articles.
There also is a need for an article singulation device, or unscrambler, which has accumulation capabilities. System requirements typically specify a package throughput which the unscrambler must meet as a normal load and a much higher rate which must be met occasionally. While it would be possible to add additional unscrambler capacity in order to size the system to handle peak load, it would be desirable to size the unscrambler to meet normal, or base, load and incorporate an accumulation function in the unscrambler.